Common Mother-of-Pearl

EASY GARDEN BUTTERFLIES

Common Mother-of-Pearl Protogoniomorpha parhassus

The Common Mother-of-Pearl is one of the Nymphalidae (Brush-footed Butterflies), subfamily Nymphalinae (Admirals, Pansies etc.).

It’s one of the biggest and flashiest butterflies found in South Africa. Its wingspan varies from 65 to 90mm. Winter forms are darker and smaller than summer forms, with more extravagantly hooked forewing tips and hindwing tails. The basic pattern of markings remains the same.

They are related to the Commodores and Diadems, and like them, tend to skulk in shady places, particularly among plants with large leaves. They venture out into the open when the sun is shining. Males perch on the upper leaves of large plants and trees with wings at 90 degrees. Occasionally one will set off and patrol his territory. This usually tempts others out of their lurking places and a graceful dance follows, the iridescent uppersides flashing green, gold, and violet in the sun. This is one of the finest sights one can see in a forest garden,

Females stay close to the host plants and lay eggs on them. Both sexes are attracted to flowers. Males are not as strongly drawn to wet mud as are the other butterflies in this group.

Distribution

Common Mother-of-Pearl occurs along the coastal littoral and lowveld from East London to northern Limpopo along the escarpment.

Although it has a limited range compared to other butterflies covered in this series, it’s such a special butterfly and worth looking out for if you live along the east coast or in the lowveld. It’s easy to attract to gardens near natural forests and its host plants are simple to cultivate.

In Africa to the north, it occurs in most forested areas south of the Sahara Desert.

Egg

The Common Mother-of-Pearl is closely related to the Commodores and Diadems and has similar, but larger, eggs. They are green, barrel-shaped, and tapered towards the top with 16 white vertical ribs that don’t reach the apex, with faint cross-ribbing. They are laid singly on young shoots of the host plant, They are about 1.1mm diameter by 1mm high. The egg stage lasts about five days.

Caterpillar

Fully-grown Common Mother-of-Pearl caterpillars are black with bands of salmon-pink on the back between the bands of spines. The head has two long, curved, spiny horns. The body has seven rows of branched spines, one per segment. These are a translucent dull yellow with a dark metallic blue base. As the larva matures the salmon-pink changes to dirty brown. Although spiny they don’t sting or make you itch. They grow from 3mm to 50-56mm long over six weeks. There are normally four moults but some individuals have five. The caterpillars hide in the shade and are almost impossible to find.

Pupa/Chrysalis

Common Mother-of-Pearl pupae are similar in shape to those of Diadems and Commodores, with short spines on the back, but the edges and spines are more pronounced and the shape more angular. The colour and markings are very reminiscent of a curled up dead leaf, which helps camouflage it because it is usually formed in the leaf debris below the plants.

The pupa is about 30mm long. The pupal stage lasts from two to three weeks depending on climate conditions.

Host plants

Common Mother-of-Pearl caterpillar host plants are in the family Acanthaceae. They have been recorded feeding on Justicia and Isoglossa species. However the main host plants in South Africa appear to be African Coromandel Asystasia intrusa in the north, and Himalayan Ruellia, Phaulopsis imbricata, elsewhere. Both grow easily from cuttings and spread well.

How to attract them

Gardeners can promote the presence of this butterfly by cultivating its preferred host plants. African Coromandel is common in coastal and lowveld gardens, but Sticky Acanth isn’t usually offered for sale by nurseries. It’s worth asking someone who has a forest garden because it takes root easily from stem cuttings. It’s also a preferred host plant for other butterflies like the Tiny Grass Blue, Zizula hylax.

Common Mother-of-Pearl, unlike its relatives, is a shade lover. In winter it often enters houses, and hides behind the curtains, or sneaks into tool sheds. It helps to plant shrubs and trees with large leaves for them to hide in. If your garden has a sunny arena surrounded by plenty of cover, on sunny days they will emerge and delight you with their antics.